New battery-free eye-tracking glasses developed at Dartmouth College could provide a more realistic augmented reality experience through hands-free input, improved controls and more accurate image displays.

Developed by researchers at Dartmouth's DartNets Lab, the new eye-tracking glasses address problems such as high power consumption and cost, which have kept eye trackers out of current augmented reality systems.

The new development uses near-infrared lights and photodiodes to create an energy-efficient, wearable system that tracks rapid eye movements and allows hands-free input of system commands.

In addition to gaming applications, the glasses can also be used to help monitor human health and is the first-ever eye tracker that can fit into everyday glasses and run without batteries.

Precise tracking of rapid eye movements is required when the eyes are used as effective input devices in human-to-computer interaction systems such as video games.

Ideally, tracking devices should be portable and consume low levels of power to eliminate frequent charging.

Existing wearable eye trackers are mostly unable to deliver high tracking performance with low energy consumption.

Most trackers use cameras to capture eye images, requiring intensive image processing and resulting in high costs and the need for external battery packs. For the new eye tracker, the Dartmouth researchers took a minimalist approach that balanced both power use and form factor.

Built with off-the-shelf hardware components and integrated into a regular pair of glasses, the prototype tracks four stages of eye movement known as fixation, smooth pursuit, saccade and blinking. Trials showed that the system achieved super high accuracy with low error for pupil tracking.

The Dartmouth eye tracker can be powered by energy harvested from indoor lighting, eliminating the need for batteries. Solar cells are placed vertically on the side of the arms of the glasses to harvest energy from indoor lighting.

The new eye tracking innovation can be used for augmented reality game and display systems. More precise tracking of eye movements could eliminate the need for hand controllers in future, and result in more efficient rendering of images by display systems.